Rapamycin (Sirolimus) is a macrocyclic lactone that has been known for use as a pharmaceutically active agent for use in treating a variety of conditions. Various related compounds, such as temsirolimus, everolimus, torin-1, torin-2, WYE-354, and metformin show similar activity, suppressing the mammalian target of rapamycin (mTOR) biochemical pathway. RAPAMUNE®, an FDA approved dosage form, is an oral dosage form of rapamycin. However, there are some conditions for which oral rapamycin is ineffective and transdermal delivery of rapamycin and/or other mTOR inhibitors would be beneficial. Accordingly, research into transdermal delivery formulations for rapamycin is ongoing.